The present invention relates to a sensor device that is designed for use in a hot environment, and a monitor with which to measure the temperature thereof during that use.
The present invention has particular efficacy, but by no means restrictively so, when used in the gas turbine field.
It is known, to measure the temperature in a gas flow through a gas turbine engine turbine section. From this, the temperature of the turbine components over which the gas flows may be assessed. An example of known art is described and illustrated in published specification GB 2 248 296, wherein an optically transparent sapphire member has a thermally emissive, metal oxide layer facing its end extremity, which layer is exposed to a flow of hot gas. Heat radiated from the layer passes through the sapphire member and a fibre optic cable, to a standard pyrometer, which translates the temperature into a useable electronic signal.
All the prior art known to the applicant for a patent for the present invention, have at least one common factor, this being that that surface which radiates the heat to the pyrometer, is immersed in the high speed gas flow, and consequently the optical receiver suffers gradually reducing ability to pass heat radiation thereto. This is brought about by exposure of the optical surface to the products of combustion, including carbon particles. A further drawback that other known heat monitors will experience, is that engines now being designed and built, will operate at temperatures higher than any previously achieved, their turbine structure being composed of materials capable of operating in those higher temperatures. Such temperatures will destroy known sensors.
The present invention seeks to provide an improved combination of a heatable sensing member and a temperature monitor therefor.
Accordingly the present invention comprises, in combination, a component operable in a hot environment and including therewithin a compartment sealed against ingress of contaminates generated in the said hot environment, and a heat monitor comprising an optic fibre located outside that space volume wherein said hot environment will occur, in spaced relationship with said component and with one end extremity aligned with an aperture in said component via which during a said hot environment operation, heat conducted into the compartment via its wall is radiated to said optic fibre end extremity for transmission thereby to a remote pyrometer.